U.S. patent number 4,478,473 [Application Number 06/431,969] was granted by the patent office on 1984-10-23 for coupling nut for an electrical connector.
This patent grant is currently assigned to The Bendix Corporation. Invention is credited to David L. Frear.
United States Patent |
4,478,473 |
Frear |
October 23, 1984 |
Coupling nut for an electrical connector
Abstract
A coupling nut (300) comprises outer and inner coupling sleeves
(320, 330) mounted for rotation about a connector shell (100)
having a plurality of ratchet teeth (150) formed on the outer
periphery of an annular shoulder thereof, a plurality of
equiangularly disposed, radially biased, lock pins (350) being
carried by inner coupling sleeve (330) during coupling and being
adapted to be cammed radially inwardly by outer coupling sleeve
(320) into a locked relation with the ratchet teeth.
Inventors: |
Frear; David L. (Afton,
NY) |
Assignee: |
The Bendix Corporation
(Southfield, MI)
|
Family
ID: |
23714208 |
Appl.
No.: |
06/431,969 |
Filed: |
September 30, 1982 |
Current U.S.
Class: |
439/312 |
Current CPC
Class: |
H01R
13/622 (20130101) |
Current International
Class: |
H01R
13/62 (20060101); H01R 13/622 (20060101); H01R
013/623 () |
Field of
Search: |
;339/DIG.2,89R,89C,89M,9R,9C ;285/82,84,86,87,92
;411/296,299,300 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: McQuade; John
Attorney, Agent or Firm: Lacina; C. D.
Claims
I claim:
1. A coupling nut for an electrical connector of the type having
first and second shells (100, 200) connectable in end-to-end
relation, one of said shells (100) including a plurality of ratchet
teeth (150) arranged annularly and extending radially outward
therefrom, the coupling nut including a cylindrical sleeve (330)
captivated for rotation about said first shell (100) and provided
with internal thread (310) for threadably connecting with
complementary external thread (210) disposed on said second shell
(200), rotation of the coupling nut drawing the shells (100, 200)
together, said coupling nut characterized by:
said cylindrical sleeve (330) being provided with an opening (338),
said opening being in register with and about said ratchet teeth
(150);
a lock pin (350) having its cross-section clearance fit within said
opening and constrained for only radial movement in said opening
(338);
bias means (370) having a portion thereof disposed against said
sleeve for constantly biasing said lock pin radially outward from
engagement with said ratchet teeth; and
drive means (320, 329) disposed for both rotational and axial
movement relative to the cylindrical sleeve for driving the
cylindrical sleeve in coupling and uncoupling directions and
driving the lock pin radially inward and into engagement with the
ratchet teeth.
2. The coupling nut as recited in claim 1, characterized by locking
means (348, 346, 162, 340) for locking said lock pin (350) within
respective ones of said ratchet teeth, said lock pin (350) being
generally cylindrical and having a medial portion (351) disposed
for reciprocation in said opening (338) and an end portion (352)
disposed radially within said sleeve (330) and adapted to engage
said ratchet teeth (150).
3. The coupling nut as recited in claim 2 wherein said cylindrical
sleeve (330) includes an annular undercut (328) and said bias means
(370) comprises a spring band (370) operatively associated
therewith and with the outer surface of said cylindrical sleeve
(330), said annular undercut (328) being disposed on the inner
surface of said sleeve and circumposing said ratchet teeth.
4. The coupling nut as recited in claim 2, said drive means (320,
329) being characterized by a second sleeve (320) coaxially
disposed and relatively rotatable about the first cylindrical
sleeve (330), and said lock pin (350) having a generally
dome-shaped head (352) disposed radially outward from the
cylindrical sleeve (330) and adapted to be normally biased against
said second sleeve (320) and a generally V-shaped tail (352)
adapted to be driven radially inward towards the one shell (100)
and fit within ones of said ratchet teeth.
5. The coupling nut as recited in claim 4, wherein said locking
means (348, 346, 162, 340) comprises an elongated slot (340)
disposed on one of said sleeves (330) being sized to receive and
captivate a bayonet-type pin (348) disposed on the other of said
sleeves (320).
6. The coupling nut as recited in claim 2, wherein six lock pins
(350) are disposed generally equilangularly around said sleeve
(330) in a clearance fit within like openings (338).
7. The coupling nut as recited in claim 5, characterized in that
said slot (340) advances said bayonet-type pin (348) in a
rotational directional contrary to the advance of said first thread
(310).
8. An electrical connector of the type comprising a cylindrical
shell (100) including an annular shoulder (140) having ratchet
teeth (150) disposed on its periphery; a first coupling sleeve
(330) rotatably mounted to said shell (100), said first coupling
sleeve (330) having a tubular forward portion (332) adapted to mate
with a compatible shell; and means for preventing rotational
movement of the coupling sleeve (330) relative to shell (100), said
means for preventing rotational movement of the coupling sleeve
being characterized by:
said first coupling sleeve (330) including an opening (338) passing
radially through the sleeve to register with said ratchet
teeth;
a second coupling sleeve (320) disposed about the first coupling
sleeve (330), the second coupling sleeve including an annular
undercut (328) disposed around said opening (338);
a lock pin (350) disposed in said opening (338);
a band (370) comprised of resilient metal biasing against said
first coupling sleeve (330) and connected to said lock pin (350)
for normally biasing the lock pin radially outwardly against the
second coupling sleeve (320); and
means (328) for driving the lock pin radially inward and into
engagement with said ratchet teeth.
9. An anti-decoupling mechanism for an electrical connector
assembly of the type having a pair of cylindrical mating shells
(100, 200) and a coupling nut (300), one of said shells (100)
including a plurality of ratchet teeth (150) arranged annularly and
extending radially outwardly around said shell, the other of said
shells (200) having a thread (210) on the outside surface thereof,
said coupling nut being rotatably mounted about said one shell
(100) and including a cylindrical coupling sleeve (330) provided
with an internal thread (310) adapted to engage the thread (210)
disposed on the other of said shells (200) so that when said
threads (210, 310) are engaged rotation of the coupling nut in one
direction draws the shells (100, 200) together, said
anti-decoupling mechanism characterized by:
lock means (350, 370, 340) for locking the coupling sleeve (330)
from rotation relative to said one shell (100), said lock means
including a lock pin (350) adapted to move radially between first
and second positions, respectively, wherein the lock pin is
disengaged and engaged with said ratchet teeth (150);
bias means (370) coupled to the lock pin for normally biasing the
lock pin into the disengaged position; and
drive means circumposed about said coupling sleeve for driving the
pin between said positions of engagement, said drive means
comprising an operating sleeve (320) including an annular cavity
defining an actuating cam (329), said bias means (370) being
disposed intermediate said operating sleeve and coupling sleeve.
Description
This invention relates to a coupling nut for an electrical
connector and more particularly to a compound coupling nut
providing a positive lock between the coupling nut and connector at
full-mate.
An electrical connector assembly is generally comprised of two
generally cylinderical connector shells, each shell retaining
therein electrical contacts with the electrical contacts of one
shell being matable with the electrical contacts in the other shell
when the connector shells are connected together by a coupling
member. The coupling member is generally rotatably mounted to one
of the connector shells by a retaining ring captivating a flange of
the coupling member adjacent a shoulder of the one connector.
During mating and unmating, electrical connectors must be easily
and quickly coupled and decoupled with use of reasonable forces.
Once mated and in use, however, the electrical connector assembly
must remain connected despite vibrational and/or other forces which
might be applied to the connector assembly and which might uncouple
the connectors. Various anti-rotation devices to prevent unwanted
back-off and/or disconnection are known.
In "Electrical Connector Assembly having an Anti-Decoupling
Mechanism" U.S. Pat. No. 4,109,990 issuing Aug. 29, 1972 Waldron et
al, a straight spring beam has its ends mounted to the coupling nut
and constantly biases a medial tooth thereof into co-acting
engagement with ratchet teeth disposed around an annular shoulder
extending from the connector shell. However, some vibration
environments may cause the straight spring beam with its tooth to
allow back-off between teeth of perhaps one or two ratchet clicks
and the connector shells to undergo axial back-off from
metal-to-metal contact resulting in hammering between connector
shells. After 500 or more cycles of constant rotational engagement
between the medial tooth and the ratchet teeth, the teeth will wear
down and the force to resist uncoupling reduced. Due to this
reduction in uncoupling force, the coupling nut will back-off more
easily during vibration exposure.
This invention provides an anti-decoupling device which promotes
locking of the coupling nut relative to its associated plug shell
after a connectable receptacle shell has achieved full mate
(metal-to-metal contact) with the plug shell. More specifically,
the anti-decoupling device comprises the coupling nut mounted to
the plug shell for rotation thereabout and comprising coaxially,
rotatably, disposed inner and outer coupling sleeves including a
plurality of generally equiangularly spaced, radially biased, lock
pins mounted in the inner coupling sleeve, each lock pin being
protectively mounted for radial movement within like support
openings disposed around the inner sleeve and circumposed about a
contiguous succession of ratchet teeth on the plug shell, the
coupling sleeves including a locking arrangement which allows the
coupling sleeve's to be driven as a unit during coupling in one
rotational direction and locks the coupling sleeves after full-mate
is achieved by further coupling direction rotation of the outer
coupling sleeve independent of the inner coupling sleeve, the
locking resulting from the lock pins being driven into engagement
with the ratchet teeth.
An advantage of the coupling nut according to this invention is
provision of a self-contained anti-decoupling device which is less
prone to vibration and prevents back off from full-mate between
connector shells. Another advantage of this invention is an
anti-decoupling device which reduces material wear during
coupling/uncoupling by actuating looking between connector shells
only when at full mate.
One way of carrying out the invention is described below with
reference to the drawings which illustrate one specific embodiment
of this invention, in which:
FIG. 1 is a side view, partially in section, of an electrical
connector assembly including a coupling nut.
FIG. 2 is an exploded view, partially in section, of the coupling
nut according to the present invention removed from one electrical
connector of the assembly.
FIG. 3 is an exploded view of a lock pin taken along lines III--III
of FIG. 2.
FIG. 4 is an end view taken along line IV--IV of FIG. 1.
FIG. 5 is a partial side view in section showing full-mate between
the electrical connector assembly.
FIG. 6 is a partial side view in section showing the connector
assembly at full mate in a locked condition.
FIG. 7 is an end view taken along lines VII--VII of FIG. 6.
Referring now to the drawings and FIG. 1 in particular, an
electrical connector assembly according to the present invention
includes coaxial first and second shells 100, 200 positioned for
mating engagement and a coupling nut 300 mounted for rotation to
first shell 100 for connecting the first shell and second shell in
mating relationship.
The first shell 100, also considered a plug-type connector,
includes a cylindrical front portion 120 having a front face 122, a
rear portion 170 and an annular shoulder 140 medially of the shell
portions, the rear portion 170 including a stepped groove 110 and
an annular wall 130 circumjacent the annular shoulder. The annular
shoulder 140 includes a front face 142, a rear face 144 and a
plurality of rachet teeth 150 on its outer circumferential surface.
The first shell also includes one or more female-type (i.e. socket)
electrical contacts 128 retained therewithin by one or more
dielectric inserts 126. The outer surface of front portion 120
includes one or more axial keys 124 for orienting first shell 100
relative to second shell 200. An annular recess 132 forwardly of
annular shoulder 140 is adapted to receive a shield spring 134 for
grounding the connector shells 100, 200 from radio frequency
interference.
The second shell 200, also considered a receptacle-type connector,
includes a front portion 220 having a front face 222, and inner
wall 223 and external thread 210 on the outside surface thereof.
Further, shell 200 includes one or more axially extending recess or
keyways 224 for receiving the respective keys 124 on first shell
100, one or more dielectric inserts 226 mounted therewithin and one
or more male-type (i.e. pin) electrical contacts 228 adapted to
mate with the socket-type contacts 128 of first shell 100, the pin
contacts 228 being retained within the dielectric inserts 226. Of
course, the pin-socket contacts 128, 228 could be other than
shown.
The coupling nut 300 is rotatably mounted on first shell 100 and
includes internal threads 310 adapted to mate with the external
threads 210 on second shell 200 to draw the first and second shells
100, 200 together with contacts 128, 228 mated. As shown, an
inwardly extending radial flange 336 on coupling nut 300 is adapted
to be received about annular wall 130 and captivated for rotation
against rear face 144 of annular shoulder 140, radial flange 336
being retained against annular shoulder 140 and the coupling nut
being retained on the shell by a retaining ring 160 received within
stepped groove 110.
Preferably and in accord with this invention, coupling nut 300 is a
compound coupling member which comprises generally cylindrical
first and second coaxial coupling sleeves 320, 330 mounted for
rotation relative to one another with the second and inner sleeve
330 including radial flange 336 and carrying a plurality of
radially movable, lock pins 350 biased by a spring member 370 from
engagement with ratchet teeth 150 but adapted to be driven into
engagement therewith for locking.
Inner coupling sleeve 330 is one-piece and comprises a tubular
shell 332 including a rearward end portion having an exterior or
first outer surface 339 and a medial shoulder 333 extending
radially outward therefrom and defining an exterior or second outer
surface 331 and a transverse end face 334 circumjacent outer
surface 339, the radial flange 336 extending radially inward from
the rearward end portion, the thread 310 being on the inner wall of
tubular shell 332 and outer surfaces 339, 331 being concentric with
one another relative to the primary axis of the coupling nut. A
plurality of openings 338 are disposed equiangularly about tubular
shell 332, each opening extending radially through outer surface
339 and sized to receive one of the lock pins 350.
Outer coupling sleeve 320 is one piece and comprises a tubular
shell 322 having an interior wall 321 and including a radial flange
326 extending radially inward from a rearward end portion thereof,
radial flange 326 defining, respectively, inner and outer end walls
325, 327. An annular undercut 328 and an annular cam 329 extend
around the interior wall 321 circumjacent inner end wall 325 of
radial flange 326, the undercut and cam being contiguous to define
an annular cavity for receiving lock pin 350 and annular undercut
328 defining a transverse end wall 324 allowing rearward axial
movement of outer coupling sleeve 320 relative to inner coupling
sleeve 330.
Retaining ring 160 is disposed against radial flanges 326, 336.
To allow sliding movement between coupling sleeves 320, 330, a
frusto-conical annular spring 162 is received in stepped groove 110
and has its rim biasing against retaining ring 160.
Two lock pins 350 are shown disposed in their respective openings
338 through inner coupling sleeve 330. Each lock pin 350, although
shown best in FIG. 3, includes a generally cylindrical body 351
having a domed end 354 for engaging undercut 328 and cam 329 and a
pointed end 352 for engaging the ratchet teeth 150. Cooperatively
attached to each lock pin 350, shown best in FIG. 3, is spring
member 370, the spring member being adapted to constantly and
consistently bias its respective lock pin radially outwardly of its
opening 338. Transverse end face 334 is adapted to position the
spring thereagainst. As shown, domed end 354 is biased outwardly
and into abutment with annular undercut 328 and pointed end 352
outwardly from engagement with the ratchet teeth. This represents
an unlocked position of coupling nut 300 relative to shells 100,
200.
Preferably and in accord with this invention a bayonet-type lock
arrangement for simultaneously locking each of the lock pins 350
into their engaged relation with respective of the ratchet teeth
150 comprises a bayonet slot 340 disposed in medial shoulder 333 of
inner coupling sleeve 330 being adapted to receive a bayonet pin
348 extending radially inwardly from outer coupling sleeve 320.
FIG. 2 shows disassembly of coupling nut 300 from plug shell 100.
Inner coupling sleeve 330 includes flange 336 having inner and
outer end walls 335, 337, respectively, with inner end wall 335
thereof being adapted to be abutted against rear face 144 of
annular shoulder 140 to position the inner coupling sleeve relative
to the plug shell.
Bayonet slot 340 is disposed within outer surface 331 of medial
shoulder 333 of coupling sleeve 330, the slot extending from
transverse end face 334 and including a humped entryway 342 at one
end and an arcuate detent 346 at the other end, entryway 242 having
transverse forward and rearward shoulders 344, 345 which define
abutment faces for captivating the bayonet pin. For effecting
coupling/uncoupling rotation, bayonet pin 348 is seated,
respectively, against forward and rearward shoulders 344, 345 and
rotation of outer coupling sleeve 320 constrains inner coupling
sleeve 330 to rotate therewith. Upon coupled engagement, bayonet
pin 348 is advanced in slot 340 to detent 346, whereby pins 350 are
driven inwardly into ratchet teeth 150 and further rotation
prevented. Annular spring 162 allows rearward movement of bayonet
pin 348 and forward bias to capture the bayonet pin 348 in detent
346. According to this invention, if coupling nut thread 310 is
right-handed, then bayonet slot 340 is right-handed and vice-versa.
Preferably three bayonet slots 340 and corresponding bayonet pins
348 would be provided equiangularly about their respective
sleeves.
Locking pin 350 and spring 370 are shown aligned for mounting
within opening 338 on inner coupling 330.
FIG. 3 is a detail view of a locking pin 350 disassembled from
spring 370. Lock pin 350 includes a generally cylindrical body 351
having domed end 354 and pointed end 352, body 351 further
including including a transverse annular slot 356 extending therein
medially of its ends. Spring member 370 includes a flat plate 372
having a pair of skirts 374 extending therefrom, flat plate 372
having extend from one edge 373 thereof a U-shaped slot 376 sized
to fit within annular slot 356 of the pin and the other edge 371 of
the skirts and plate being adapted to abut the transverse end face
334 to secure spring member 370 and lock pin 350 together.
FIG. 4 is an end view through the plug shell 100 showing detail of
coupling nut 300 in the unlocked position. Six lock pins 350 are
equiangularly disposed around the plug shell, each pin having its
domed end 354 biased by skirts 374 into abutment against annular
undercut 328 and pointed end 352 out of engagement with the ratchet
teeth 150 disposed on annular shoulder 140, the ratchet teeth
forming, respectively, a contiguous succession of peaks and valleys
154, 152, with valleys 152 being sized to receive pointed ends 352
of lock pin 350 for providing the locked position.
FIG. 5 shows a full mate condition wherein end face 222 of
receptacle shell 200 has been drawn within coupling nut 300 and
into abutment (i.e. metal-to-metal contact) with forward face 142
of annular shoulder 140 around plug shell 100. Each of the lock
pins 350 are in their unlocked position and biased radially
outwardly in openings 338 from engagement with ratchet teeth
150.
FIG. 6 shows the full-mate condition wherein lock pins 350 are in
locked engagement in respective valleys 152 of ratchet teeth 150.
Outer coupling sleeve 320 has been rotated in the coupling
direction and advanced longitudinally forward relative to inner
coupling sleeve 330, resulting in bayonet pin 348 being advanced
through its slot 340 and into detent 346. As a result of outer
sleeve 320 being rotated forward relative to inner coupling sleeve
330, annular undercut 328 and cam 329 advance forwardly with the
cam 329 driving the lock pins 350 downwardly (i.e. radially inward)
and into engagement with ratchet teeth 150.
FIG. 7 shows an end view of the locked full-mate condition. Skirts
374 have been flattened against outer surface 339 of inner coupling
sleeve 330 and pointed ends 352 of lock pins 350 driven into their
respective valleys 152 of ratchet teeth 150.
Coupling nut 300 would be assembled by sliding inner coupling
sleeve 330 over rear portion 170 of plug shell 100 and abutting its
radial flange 337 against rear face 144 of annular shoulder 140;
assembling spring member 370 with lock pins 350 by inserting the
U-shaped slot 376 of spring member 370 into the annular slot 356 of
lock pin 350; radially inserting cylindrical bodies 351 of each
lock pin 350 into openings 338 of inner coupling sleeve 330;
sliding outer coupling sleeve 320 over inner coupling sleeve 330,
the domed ends 354 positioning themselves within the annular cavity
and against annular undercut 328; advancing bayonet pin 348 into
entryway 342 against abutment shoulders 344, 345; sliding retaining
ring 160 over rear portion 170 of the plug shell and into abutment
with radial flanges 326, 336; and captivating the assembly with
annular spring 162 being received in stepped groove 110.
To complete an electrical connector assembly, the shells 100, 200
would be positioned so that keys and keyways 124, 224 are aligned
and then axially advanced towards each other until the thread 210
on the receptacle shell 200 is engaged by the thread 310 on the
inner coupling sleeve 330. Rotation of coupling nut 300, shown best
in FIGS. 5 and 6, axially advances front portion 120 of the first
shell inwardly into front portion 220 of the second shell, inner
wall 223 of the second shell 200 compressing shield 134 into
annular recess 136 with continued advance of the shell front
portions 120, 220 advancing front face 222 into abutment against
front face 142 of annular shoulder 140 when the full mate condition
is achieved.
Bayonet pin 348 functions first to drive the coupling sleeves 320,
330 together as a unit during coupling/uncoupling direction
rotation and second to actuate locking relation between the sleeves
and first connector shell 100. Forward axial motion results from
bayonet pin 348 being driven against forward shoulder 344 within
humped entryway 342. As a result of this rotation, the shells 100,
200 do not corotate relative to one another but are axially drawn
towards one another until end face 222 of the receptacle shell 200
is in metal-to-metal contact with the plug shell 100. Longitudinal
rearward sliding motion of bayonet pin 348 over the hump of
sufficient magnitude to overcome the forward bias of annular spring
162 drives the outer sleeve 320 slightly rearwardly relative to
inner sleeve 330 which allows the bayonet pin to be driven
longitudinally forward in slot 340. Forward advance of outer sleeve
320 advances annular cam 329 forwardly and into contact with lock
pins 350, this contact driving the lock pins radially inward and
into engagement with ratchet teeth 150. Bayonet pin 348 is advanced
through through slot 340 and into register with arcuate detent 346
where upon annular spring 162 drives the outer coupling sleeve 320
forwardly relative to inner coupling sleeve 330 whereby the bayonet
pin 348 is captured in the detent. Contact between forward faces of
dielectric inserts 126, 226 provides a slight rearward bias against
the shells 100, 200, providing resistance which the bayonet pin
must overcome to move forwardly and from its detent.
Although the description of this invention has been given with
reference to a particular embodiment, it is not to be construed in
any limiting sense, many variations and modifications possibly
occurring to those skilled in the art. For example, the bayonet
slot 340 could require left-handed advance of bayonet pin 348
relative to right-handed coupling advance of the inner coupling
sleeve 330.
* * * * *